<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
.parent {
    position: relative;
}
.child {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.parent {
    display: flex;
    justify-content: center;
    align-items: center;
}

.parent {
position: relative;
}
.child {
position: absolute;
top: 0;
bottom: 0;
left: 0;
right: 0;
margin: auto;
}
  </style>
</head>
<body>
  <!-- [css] 怎么才能让图文不可复制？ -->  
  <!-- 禁止用户选择 -->
  -webkit-user-select: none;
-ms-user-select: none;
-moz-user-select: none;
-khtml-user-select: none;
user-select: none;
</body>


<body>
</body>

</html>